The present invention relates to a novel preventive and curative medicament against infection with influenza virus or, more particularly, to a preventive and curative medicament against infection with influenza viruses of the type A and type B.
As is well known, influenza is an important disease of mankind which has attacked human beings periodically in the past and up to now and sometimes loads to death, e.g., more than ten million people died in one epidemic. By virtue of the great improvement in the nutrition and hygienic conditions, along with the rapid progress of the medical technology to overcome other infectious diseases in recent years, the menace by the influenza infection is no longer so great as in the past. Nevertheless, many and unspecified people are infected with the influenza viruses by airborne infection to cause one or more epidemics every year.
Many medicaments have been hitherto proposed to prevent infection with influenza viruses but none of them can exhibit fully satisfactory preventive effects. The method considered to be most effective for prevention against infection with influenza virus in these days is inoculation of vaccine. A problem in the vaccination against influenza, however, is that great difficulties are encountered, despite the relatively low probability of success, in the development works for a new influenza vaccine in order to comply with the unceasingly occurring mutation of the antigen of the influenza virus. Accordingly, it is eagerly desired to develop a novel preventive and curative medicament against infection with the influenza virus having the following properties: (1) capable of effectively exhibiting the desired preventing effect, regardless of the antigenicity of the virus and (2) usable without problems of safety due to absence of any harmful side effects against human body.